A sleep hormone produced by the pineal gland may improve sleep issues in children with autism, resulting in an improvement of the day to day dynamics for the entire family.
Americans are tired. About 40 million suffer from a chronic sleep disorder, with an additional 20-30 million affected by intermittent sleep-related problems. Yet for children with autism the problem is even more common, resulting in an issue that negatively impacts the day to day dynamics of the whole family. Researchers estimate that between 40% and 80% of children with autism have difficulty sleeping or staying asleep.
Autism Associated with Higher Incidence of Sleep Disorders
Dr. Beth Maslow, Associate Professor of Neurology and Director of Vanderbilt Sleep Disorders Center reports that sleep disorder diaries completed by parents of children with autism revealed that the most common sleep concern is insomnia which may include:
- Prolonged time to fall asleep/difficulty falling asleep
- Inconsistent sleep routines
- Decreased sleep duration and continuity
- Restlessness or poor sleep quality
- Increased arousals and awakenings
- Early morning wake time
In her 2007 presentation, “Promoting Sleep in Children with Autism Spectrum Disorders,” Dr. Maslow outlined other sleep issues children with autism may experience such as sleep disordered breathing, bruxism, arousals from sleep with confusion or wandering, rhythmic movement disorder, leg movements and daytime sleepiness.
While the sleep disorder estimates are high in children with autism, Dr. Maslow reports that only 54% of parents surveyed indicated their child had a sleep problem (Honomichl and Anders 2002). Yet for those families affected by autism who do struggle with nighttime slumber, the cumulative effects of sleep deprivation trickle down, wreaking havoc on the family’s emotional and physical well-being, and exacerbating behavioral issues the child may already exhibit.
“Sleep onset problems at the beginning of the night are very troublesome for children and their families,” says Beth L. Goodlin-Jones of the M.I.N.D Institute at the University of California Davis Health System in Sacramento, “Sometimes children may take one to two hours to fall asleep and often they disrupt the household during this time,” says Goodlin-Jones.
Autism and Sleep Have Neurochemistry Connection
Scientists aren’t quite sure why autistic children tend to have sleep problems, although several theories exist.
Children with autism don’t always pick up on social cues, including those from siblings and parents that signal when it’s time to go to bed; many have increased sensitivity to stimuli such as touch or sound that may keep them awake, and some kids with autism struggle with anxiety issues which disrupt their sleep patterns.
Another theory is the relationship between the biochemistry of sleep and the brain imbalances associated with autism. Dr. Maslow reports that abnormalities in serotonin, GABA and melatonin, (three neurotransmitters involved in the sleep-wake cycle), are associated in people with autism.
Serotonin for example, promotes sleep by dampening cortical arousal systems or by stimulating the accumulation of hypothalamic sleep factors. Research has shown people with autism tend to have problems with serotonin synthesis, metabolism, and transport as well as GABAeric interneuron disruption (Levitt, 2004).
Melatonin Promising for Children with Autism and Insomnia
Melatonin, a hormone produced by the pineal gland in the brain, is a critical factor involved in regulating the sleep-wake cycle and to promote sleep.
People with autism, research shows, often have deficiencies in melatonin secretion and excretion (Nir, 1995; Kulman, 2000;Tordjman,2005). Autism’s association with problems with sleep latency (falling asleep) and decreased sleep time, coincides with a disruption in the circadian rhythm regulated by melatonin.
In a study reported in the Journal of Child Neurology, Dr. Malow and her colleagues reviewed the medical records of 107 children with autism, ages 2-18, who tried varying dosages of melatonin for insomnia. The results indicated that 25% of parents reported their children no longer had sleep concerns, 60% reported the sleep problems improved, 13% still had major concerns and only 1 percent (one child) had worse symptoms. Only three of the 107 children studied reported mild side effects.
Researchers in the April 2009 issue of the Journal of Clinical Sleep Medicine reported that melatonin medication decreased the length of time it takes for children with autistic spectrum disorder (ASD), Fragile X Syndrome (FXS), or both to fall asleep at the beginning of the night.
Children in the study experienced significant improvements in total night sleep durations, sleep latency times, and sleep-onset times. Mean sleep duration was longer on melatonin than placebo by 21 minutes, sleep-onset latency was shorter by 28 minutes and sleep-onset time was earlier by 42 minutes.
In addition, in a June 2010 study involving twenty-two children with autism spectrum disorders, melatonin significantly improved sleep latency (by an average of 47 min) and total sleep (by an average of 52 min) compared to placebo. It did not however, decrease the number of night wakenings.
“Rather than treating them [the kids] with some other drug that would promote sleep, [we could] give them what they’re missing,” said Dr. Malow. She noted that melatonin is very appealing to parents because “it’s something natural that’s already in your child’s body.”
“Although prospective trials will be needed to determine if melatonin is an effective sleep aid in this population, this study does support that it may be a reasonable treatment option in these children when administered under the care of a physician and combined with behavioral therapies for sleep,” Malow said in a 2008 press release for Vanderbilt Medical Center.
Autism Speaks, in conjunction with the Dana Foundation, is contributing funds to a study led by Malow and McGrew. The study is tracking how sleep patterns change in children with autism with the introduction of melatonin. Results are being measured by parent reports and a method called actigraphy which monitors sleep by tracking movements at night via a wristwatch-like device.
So far all children completing the trial have had better sleep, improved daytime behavior, and parents reporting they’re coping better with their child’s autism, said Dr. Malow.
While additional and long term research needs to be conducted, results look promising for the use of melatonin to improve sleep latency and duration in children with autism, and in response, to improving the overall day to day family dynamics.
Honomichl RD, Goodlin-Jones BL., Burnham M., Gaylor E.and Anders T F. “Sleep patterns of children with pervasive developmental disorders.” Journal of Autism and Developmental Disorders. 2002.
Guénolé F., Baleyte J. “Effectiveness of melatonin for sleep problems in autism spectrum disorders: Evidence grows but research is still needed.” Journal of Autism and Developmental Disorders. Sept 24, 2010.
Malow, Beth, M.D. “Melatonin Well-Tolerated Sleep Aid In Children With Autism.” February 8,2008.
Wright B, Sims D, Smart S, Alwazeer A, Alderson-Day B, Allgar V, Whitton C, Tomlinson H, Bennett S, Jardine J, McCaffrey N, Leyland C, Jakeman C, Miles J.”Melatonin Versus Placebo in Children with Autism Spectrum Conditions and Severe Sleep Problems Not Amenable to Behaviour Management Strategies: A Randomised Controlled Crossover Trial.” Journal of Autism and Developmental Disorders. June 2010.
Researchers are continuing to piece together one of the most mysterious modern day epidemics, autism spectrum disorder, a syndrome affecting one in 110 children. A growing body of evidence suggests low vitamin D levels may play a role.
Scientists studying autism and vitamin D believe there may be an association between a woman’s vitamin D levels during pregnancy, her child’s subsequent vitamin D levels, and autism symptoms. Researchers aren’t however, suggesting a vitamin D deficiency causes autism, rather that a number of incidental studies suggest a link.
Autism Epidemic Presents Five Unexplained Features
The Autism Society of America (ASA) describes autism as “a complex developmental disability that typically appears during the first three years of life and is the result of a neurological disorder that affects the normal functioning of the brain, impacting development in the areas of social interaction and communication skills.” Autism is considered a spectrum disorder because it impacts individuals differently and to varying degrees.
ASA estimates 1 to 1.5 million Americans are impacted by autism, making it a national health crisis costing about $35 billion annually. Yet, despite numerous exhaustive metabolic and genetic evaluations conducted by scientists all over the world, researchers still aren’t able to pinpoint the exact causes.
Dr. John Cannell, Executive Director of the Vitamin D Council, writes that scientific groups have been trying to account for the 20-year increase in autism. Yet any valid theory says Cannell, must account for the following five unexplained features:
- significantly higher concordance (if one has it, the other is likely to have it) rates in identical, but not fraternal, twins
- widely-varying symptoms, even among identical twins
- striking 4:1 male to female sex ratio
- increased rates in blacks
- rapid increase in occurrence rates over the last 20 years
A 2009 Scientific American article “What if Vitamin D Deficiency is a Cause of Autism?” reported that five researchers at Harvard endorsed the vitamin D theory of autism, and that Dr. Darryl Eyles with the University of Queensland joined the expanding list of scientists who support the theory.
Despite the name, “vitamin” D is a secosteroid hormone that directly regulates more than 1,000 human genes. Not readily available in foods, vitamin D is made in large quantities when sunlight strikes bare skin.
Vitamin D Regulates Long List of Genes
Geneticists believe that genetic codes may not properly transfer in children with autism, and that multiple genes aren’t expressed, possibly the result of environmental injury. Vitamin D, it seems, may protect an individual’s genome (entire genetic material) from damage from environmental toxins.
Researchers with the Autism Genetic Resource Exchange (AGRE) identified mutations in four genes within the AGRE families. Two of the genes were shown to be associated with autism and often are involved in forming or maintaining neural synapses, the point of connection between individual neurons. One of the new genes identified was neural cell adhesion molecule 2 (NCAM2). NCAM2 is expressed in the hippocampus of the human brain, a region previously associated with autism.
Dr. Lei, lead researcher on the study, explains the implications, “Studies such as this provide evidence that autism is a genetically based disease that affects neural connectivity.”
Dr. Cannell emphasizes that the vitamin D theory of autism doesn’t downplay the genetic role. In fact, he writes, “Without the genetic tendency for autism, I suspect that severe maternal or early childhood vitamin D deficiency may cause bone abnormalities, as referenced above, [but] with no evidence autism.” A vitamin D deficiency during pregnancy and early childhood may, however, trigger symptoms in a child who is genetically pre-disposed to the disorder.
Autism and Vitamin D Deficiency Linked Through Incidental Findings
In the May 2010 issue of Acta Pædiatrica, Dr. Cannell submitted a paper stating his position regarding D’s role in autism, “I have suggested that the primary environmental trigger for autism is not vaccinations, toxins or infections, but gestational and early childhood vitamin D deficiency (1,2),” he writes.
In the report, Cannell cited several studies that offer incidental evidence (unexpected clinical findings) of a link between D deficiency and autism:
A few of the findings include:
- Boys with autism have unexplained metacarpal bone thickness. At some point these boys developed less cortical bone than normal children, a finding consistent with undetected and untreated childhood or even intrauterine vitamin D deficiency.
- Melanin in the skin is an effective sunblock. Melanin is higher in dark-skinned people. Three of four recent U.S. studies found a higher incidence of autism in black children.
- A Somali immigrant study in Sweden found a higher rate of autism in the Somalian population. These refugees traded family compounds and regular exposure to the equatorial sun for cloistered high-rise apartments, and many of them Muslim, cover their bodies from head to toe (thus received minimal sun exposure).
- Studies showed autism in three U.S. states was higher in areas with more precipitation and clouds (less exposure to sunlight).
- Lower seafood consumption during pregnancy was associated with low verbal intelligence quotient, suboptimum outcomes for prosocial behavior, fine motor, communication and social development scores. Fish is one of the few foods with significant amounts of vitamin D.
- Autism is more common in mothers who take antiepileptic drugs. Antiepileptic drugs are one of the few classes of drugs that interferes with vitamin D metabolism, lowering 25(OH)D levels.
While the government’s advice to the public over the past few decades to use sunblock and to avoid excessive sun exposure to reduce the incidence of skin cancer was well-intentioned, an unfortunate side effect has contributed to two modern day epidemics, vitamin D deficiency and autism spectrum disorder.
“Study adds to evidence that autism has genetic basis,” ScienceDaily, May 3, 2010. Accessed July 23, 2010.
Cannell JJ. “On the Aetiology of Autism.” Acta Paediatrica. May 2010.
Cannell JJ.” Autism and Vitamin D,” Medical Hypotheses 2008, Accessed July 23,2010.
Lite, J., “Vitamin D deficiency soars in the U.S.,” Scientific American, March 23, 2009. Accessed July 23,2010.
Copyright Laura Owens. Contact the author to obtain permission for republication.